While the locations of Har Grizim and Har Evel are explicitly described, the location of Har Habayis is left for us to find. The place of the Beis Hamikdash is undefined, and Avraham Avinu is the first to discover it. When we daven, we turn to the place of the mikdash. It is important for a person to establish a specific place for prayer. One who does so is considered to be a student of Avraham Avinu, who was the original one to find the place of kedusha. In Beis El, Avraham brought down the presence of Hashem. Through our tefillah, which is a creative act, we try to do the same, bringing Hashem down onto this world.